The detection of abnormal masses in mammograms

Recursive median filtering can be applied to images at a number of scales and orientations giving a scale space description at a pixel level. The resulting scale-orientation signatures can be used to discriminate between different structures, most easily between linear and blob-like structures, but also to describe any remaining texture in the image. As a specific example, the technique is applied to mammography, in the detection of mass-like structures associated with spiculated lesions. For structures of diameter 12mm, a sensitivity of 80% is achieved with 0.25 false positives per image, which compares favourably with the best results found in the literature.